The（）has a built-in world map; most areas are displayed on a scale of 4000 nm from the top to the bottom of the screen，and can be zoomed in to 150 nm.

The development of（）led to the fully automatic ARPA systems installed on commercial ships.

You are underway at 5 knots and see on your radar a contact 10 miles directly astern of you. 12 minutes later，the contact is 8 miles directly astern of you. What is the estimated speed of the contact? （）

Your radar is set on a true motion display.Which of the following will NOT appear to move across the PPI scope（）.

You are using a radar in which your own ship is shown at the center，and the heading flash always points to 0°. If bearings are measured in relation to the flash，what type of bearings are produced? （）

Although manual plotting for CPA works well，the workload can become overwhelming when confronted with（）.

When using a radar in a unstabilized mode，fixes are determined most easily from（）.

You are underway in thick fog. You have not determined if risk of collision exists. Which statement is TRUE?（）.

Which ARPA data should you use in order to determine if a close quarters situation will develop with a target vessel? （）

What provides little or no indication that a vessel is dragging anchor? （）